The invention relates to a method and an HMI system for controlling and monitoring a technical installation.
Technical installations include all types of technical equipment and systems, both individually in stand-alone arrangements and interconnected in data networks, e.g., via a field bus. In industrial applications, such technical installations include individual apparatuses, such as drives and processing machines. However, a technical installation can also be a production plant, in which an entire technical process is operated by locally distributed control apparatuses. Such a production facility is, for example, a chemical facility or an assembly line. Technical installations are controlled and operated by special digital data processing systems, which are also referred to as automation systems. Such systems include devices for the direct control of the technical installation, i.e., programmable logic controllers or PLCs. To relieve these controllers, automation systems have other special devices that form an interface for operator personnel. These devices are called “control and monitoring” devices, (“C&M” for short), or HMI devices, i.e., human machine interfaces.
The term “HMI device” is a generic term and includes all the components belonging to this group of devices, such as, e.g., operator panels (OP for short). These operator panels can be stationary or mobile devices. In a networked automation system, operator personnel use HMI devices to display and control process data of the technical installation to be controlled. This function is referred to as “supervisory control and data acquisition” (SCADA). For this purpose, the HMI device usually has a special hardware structure, i.e., it is provided, for example, with a touch screen and is specially shielded against environmental influences. The HMI devices also use a special type of software, which provides functions to improve operational ease of use, quality and safety when the HMI devices are operated by an operator. For example, HMI devices can visualize, control, design and generate interactive process images or representations of the technical installation to be controlled. This makes it possible to selectively display responses of the technical installation, typically in the form of measured values and messages. In addition, specific operator actions and data inputs make it possible to bring the technical installation into desired states.
Conventionally, the devices of an automation system are fixedly assigned to the technical installation to be controlled. These devices include not only the control devices that are fixedly coupled to the technical installation, but, typically, also the HMI devices. The devices are usually uniquely assigned to the associated technical installation as a fixed component of the respective automation system, e.g., in the form of a terminal or an operator panel. All the machine and control specific data of the respectively associated technical installation, e.g., machine data, process images or representations, configuration files and much more, are loaded into the individual operator panels of an automation system. The runtime software of such an HMI device thus contains all the data and parameters necessary for the operator personnel to control and monitor precisely this technical installation or a part thereof.
However, such a fixed, data-related allocation or assignment of an HMI device to an automation system and the technical installation connected thereto has drawbacks. Since all the machine and control specific data of the installation is fixedly stored in the HMI device, the flexibility of such an HMI device is usually limited. Therefore, these HMI devices are often stationary and mounted in the immediate spatial environment of the associated technical installation. Thus, an operator has to go to the location of the respective HMI device and is therefore limited in his or her freedom to move. Furthermore, both the HMI device and the operator are continuously exposed to the environmental conditions present at the mounting site.
If such an HMI device must be replaced, all the machine and control specific data must be reloaded in order to completely restore the operability of the original HMI device. Even if the HMI devices are mobile, e.g., in the form of cable-bound or radio-linked handheld devices, they are typically allocated or assigned to a technical installation or to a control apparatus thereof in logically unique manner. Again, this typically means that all the design, display and machine data has to be loaded into the handheld device; i.e., the data must be kept available for all possible monitoring and control situations, irrespective of how frequently the data is actually used. As a consequence, the hardware and software for such HMI devices must be powerful enough and, thus, if such devices fail and have to be replaced, significant costs may be incurred.